Visual analogue scales in stroke: what can they tell us about health-related quality of life?

OBJECTIVES: Contrasting accounts exist on whether people with stroke are able to self-report on outcomes using visual analogue scales (VASs). We explored correlations between multi-item scale-rated health-related quality of life (HRQL) and VAS-rated HRQL after stroke, and compared those with versus without aphasia. DESIGN: Cross-sectional survey. SETTING: Community dwelling stroke patients living in London. PARTICIPANTS: People with first stroke were recruited during their hospital stay and were assessed 3 months later. MEASURES: The Frenchay Aphasia Screening Test, the Stroke and Aphasia Quality of Life Scale (SAQOL-39g) and a single vertical VAS. RESULTS: 73 people took part, 14 with aphasia. VAS scores were significantly correlated with the overall SAQOL-39g (r=0.69, p<0.01). SAQOL-39g subdomain scores were also correlated with VAS scores, with the psychosocial domain most highly correlated (r=0.67, p<0.01) and the communication least correlated (ρ=0.30, p<0.05). SAQOL-39g-VAS difference scores were higher for people with aphasia and the difference was significant (t (71)=2.02, p<0.05). CONCLUSIONS: Despite the significant correlation of the overall SAQOL-39g and the VAS-rated HRQL, subdomain results suggested that people considered mostly psychosocial aspects when rating their HRQL on a single VAS. Agreement was poorer for people with aphasia, raising issues for the use of VASs with people with aphasia.